What is it that makes billionaires predictable in their tastes? Sub-volcanic lair? Check. Submarine cars? Yep. And just like Howard Hughes in The Aviator, Microsoft co-founder Paul Allen has rolled out the world’s biggest airplane.

Stratolaunch Systems Corp.

Stratolaunch is Allen’s company created to send satellites into orbit using an Orbital ATK Pegasus XL rocket carried high aloft by the world’s biggest airplane instead of starting at sea level, letting it start high above most of the atmosphere.

Stratolaunch Systems Corp.

Orbital already launches Pegasus XL rockets using a converted Lockheed L-1011 TriStar jumbo jet, but Stratolaunch will be able to carry three of the rockets for launch on each flight!

Stratolaunch Systems Corp.

This monster stretches 385 feet from wingtip to wingtip and is 238 feet long. Power comes from six Pratt & Whitney PW4056 jet engines, the kind that the Boeing 747 jumbo jet uses, but that plane only has four of them.

The combination of massive jet thrust and a huge wingspan let the Stratolaunch plane lift a mind-boggling half-million pounds of payload, which is good considering it has to carry three rockets.

This colossus hasn’t yet taken wing. The rollout from its hanger was just the public debut for fueling tests. Demonstration flights are scheduled for 2019. After that, Allen will have to start looking into getting a submarine.